Merge branch 'tg/test-index-v4' into maint
[git] / builtin / grep.c
1 /*
2  * Builtin "git grep"
3  *
4  * Copyright (c) 2006 Junio C Hamano
5  */
6 #include "cache.h"
7 #include "blob.h"
8 #include "tree.h"
9 #include "commit.h"
10 #include "tag.h"
11 #include "tree-walk.h"
12 #include "builtin.h"
13 #include "parse-options.h"
14 #include "string-list.h"
15 #include "run-command.h"
16 #include "userdiff.h"
17 #include "grep.h"
18 #include "quote.h"
19 #include "dir.h"
20 #include "pathspec.h"
21
22 static char const * const grep_usage[] = {
23         N_("git grep [options] [-e] <pattern> [<rev>...] [[--] <path>...]"),
24         NULL
25 };
26
27 static int use_threads = 1;
28
29 #ifndef NO_PTHREADS
30 #define THREADS 8
31 static pthread_t threads[THREADS];
32
33 /* We use one producer thread and THREADS consumer
34  * threads. The producer adds struct work_items to 'todo' and the
35  * consumers pick work items from the same array.
36  */
37 struct work_item {
38         struct grep_source source;
39         char done;
40         struct strbuf out;
41 };
42
43 /* In the range [todo_done, todo_start) in 'todo' we have work_items
44  * that have been or are processed by a consumer thread. We haven't
45  * written the result for these to stdout yet.
46  *
47  * The work_items in [todo_start, todo_end) are waiting to be picked
48  * up by a consumer thread.
49  *
50  * The ranges are modulo TODO_SIZE.
51  */
52 #define TODO_SIZE 128
53 static struct work_item todo[TODO_SIZE];
54 static int todo_start;
55 static int todo_end;
56 static int todo_done;
57
58 /* Has all work items been added? */
59 static int all_work_added;
60
61 /* This lock protects all the variables above. */
62 static pthread_mutex_t grep_mutex;
63
64 static inline void grep_lock(void)
65 {
66         if (use_threads)
67                 pthread_mutex_lock(&grep_mutex);
68 }
69
70 static inline void grep_unlock(void)
71 {
72         if (use_threads)
73                 pthread_mutex_unlock(&grep_mutex);
74 }
75
76 /* Signalled when a new work_item is added to todo. */
77 static pthread_cond_t cond_add;
78
79 /* Signalled when the result from one work_item is written to
80  * stdout.
81  */
82 static pthread_cond_t cond_write;
83
84 /* Signalled when we are finished with everything. */
85 static pthread_cond_t cond_result;
86
87 static int skip_first_line;
88
89 static void add_work(struct grep_opt *opt, enum grep_source_type type,
90                      const char *name, const char *path, const void *id)
91 {
92         grep_lock();
93
94         while ((todo_end+1) % ARRAY_SIZE(todo) == todo_done) {
95                 pthread_cond_wait(&cond_write, &grep_mutex);
96         }
97
98         grep_source_init(&todo[todo_end].source, type, name, path, id);
99         if (opt->binary != GREP_BINARY_TEXT)
100                 grep_source_load_driver(&todo[todo_end].source);
101         todo[todo_end].done = 0;
102         strbuf_reset(&todo[todo_end].out);
103         todo_end = (todo_end + 1) % ARRAY_SIZE(todo);
104
105         pthread_cond_signal(&cond_add);
106         grep_unlock();
107 }
108
109 static struct work_item *get_work(void)
110 {
111         struct work_item *ret;
112
113         grep_lock();
114         while (todo_start == todo_end && !all_work_added) {
115                 pthread_cond_wait(&cond_add, &grep_mutex);
116         }
117
118         if (todo_start == todo_end && all_work_added) {
119                 ret = NULL;
120         } else {
121                 ret = &todo[todo_start];
122                 todo_start = (todo_start + 1) % ARRAY_SIZE(todo);
123         }
124         grep_unlock();
125         return ret;
126 }
127
128 static void work_done(struct work_item *w)
129 {
130         int old_done;
131
132         grep_lock();
133         w->done = 1;
134         old_done = todo_done;
135         for(; todo[todo_done].done && todo_done != todo_start;
136             todo_done = (todo_done+1) % ARRAY_SIZE(todo)) {
137                 w = &todo[todo_done];
138                 if (w->out.len) {
139                         const char *p = w->out.buf;
140                         size_t len = w->out.len;
141
142                         /* Skip the leading hunk mark of the first file. */
143                         if (skip_first_line) {
144                                 while (len) {
145                                         len--;
146                                         if (*p++ == '\n')
147                                                 break;
148                                 }
149                                 skip_first_line = 0;
150                         }
151
152                         write_or_die(1, p, len);
153                 }
154                 grep_source_clear(&w->source);
155         }
156
157         if (old_done != todo_done)
158                 pthread_cond_signal(&cond_write);
159
160         if (all_work_added && todo_done == todo_end)
161                 pthread_cond_signal(&cond_result);
162
163         grep_unlock();
164 }
165
166 static void *run(void *arg)
167 {
168         int hit = 0;
169         struct grep_opt *opt = arg;
170
171         while (1) {
172                 struct work_item *w = get_work();
173                 if (!w)
174                         break;
175
176                 opt->output_priv = w;
177                 hit |= grep_source(opt, &w->source);
178                 grep_source_clear_data(&w->source);
179                 work_done(w);
180         }
181         free_grep_patterns(arg);
182         free(arg);
183
184         return (void*) (intptr_t) hit;
185 }
186
187 static void strbuf_out(struct grep_opt *opt, const void *buf, size_t size)
188 {
189         struct work_item *w = opt->output_priv;
190         strbuf_add(&w->out, buf, size);
191 }
192
193 static void start_threads(struct grep_opt *opt)
194 {
195         int i;
196
197         pthread_mutex_init(&grep_mutex, NULL);
198         pthread_mutex_init(&grep_read_mutex, NULL);
199         pthread_mutex_init(&grep_attr_mutex, NULL);
200         pthread_cond_init(&cond_add, NULL);
201         pthread_cond_init(&cond_write, NULL);
202         pthread_cond_init(&cond_result, NULL);
203         grep_use_locks = 1;
204
205         for (i = 0; i < ARRAY_SIZE(todo); i++) {
206                 strbuf_init(&todo[i].out, 0);
207         }
208
209         for (i = 0; i < ARRAY_SIZE(threads); i++) {
210                 int err;
211                 struct grep_opt *o = grep_opt_dup(opt);
212                 o->output = strbuf_out;
213                 o->debug = 0;
214                 compile_grep_patterns(o);
215                 err = pthread_create(&threads[i], NULL, run, o);
216
217                 if (err)
218                         die(_("grep: failed to create thread: %s"),
219                             strerror(err));
220         }
221 }
222
223 static int wait_all(void)
224 {
225         int hit = 0;
226         int i;
227
228         grep_lock();
229         all_work_added = 1;
230
231         /* Wait until all work is done. */
232         while (todo_done != todo_end)
233                 pthread_cond_wait(&cond_result, &grep_mutex);
234
235         /* Wake up all the consumer threads so they can see that there
236          * is no more work to do.
237          */
238         pthread_cond_broadcast(&cond_add);
239         grep_unlock();
240
241         for (i = 0; i < ARRAY_SIZE(threads); i++) {
242                 void *h;
243                 pthread_join(threads[i], &h);
244                 hit |= (int) (intptr_t) h;
245         }
246
247         pthread_mutex_destroy(&grep_mutex);
248         pthread_mutex_destroy(&grep_read_mutex);
249         pthread_mutex_destroy(&grep_attr_mutex);
250         pthread_cond_destroy(&cond_add);
251         pthread_cond_destroy(&cond_write);
252         pthread_cond_destroy(&cond_result);
253         grep_use_locks = 0;
254
255         return hit;
256 }
257 #else /* !NO_PTHREADS */
258
259 static int wait_all(void)
260 {
261         return 0;
262 }
263 #endif
264
265 static int grep_cmd_config(const char *var, const char *value, void *cb)
266 {
267         int st = grep_config(var, value, cb);
268         if (git_color_default_config(var, value, cb) < 0)
269                 st = -1;
270         return st;
271 }
272
273 static void *lock_and_read_sha1_file(const unsigned char *sha1, enum object_type *type, unsigned long *size)
274 {
275         void *data;
276
277         grep_read_lock();
278         data = read_sha1_file(sha1, type, size);
279         grep_read_unlock();
280         return data;
281 }
282
283 static int grep_sha1(struct grep_opt *opt, const unsigned char *sha1,
284                      const char *filename, int tree_name_len,
285                      const char *path)
286 {
287         struct strbuf pathbuf = STRBUF_INIT;
288
289         if (opt->relative && opt->prefix_length) {
290                 quote_path_relative(filename + tree_name_len, opt->prefix, &pathbuf);
291                 strbuf_insert(&pathbuf, 0, filename, tree_name_len);
292         } else {
293                 strbuf_addstr(&pathbuf, filename);
294         }
295
296 #ifndef NO_PTHREADS
297         if (use_threads) {
298                 add_work(opt, GREP_SOURCE_SHA1, pathbuf.buf, path, sha1);
299                 strbuf_release(&pathbuf);
300                 return 0;
301         } else
302 #endif
303         {
304                 struct grep_source gs;
305                 int hit;
306
307                 grep_source_init(&gs, GREP_SOURCE_SHA1, pathbuf.buf, path, sha1);
308                 strbuf_release(&pathbuf);
309                 hit = grep_source(opt, &gs);
310
311                 grep_source_clear(&gs);
312                 return hit;
313         }
314 }
315
316 static int grep_file(struct grep_opt *opt, const char *filename)
317 {
318         struct strbuf buf = STRBUF_INIT;
319
320         if (opt->relative && opt->prefix_length)
321                 quote_path_relative(filename, opt->prefix, &buf);
322         else
323                 strbuf_addstr(&buf, filename);
324
325 #ifndef NO_PTHREADS
326         if (use_threads) {
327                 add_work(opt, GREP_SOURCE_FILE, buf.buf, filename, filename);
328                 strbuf_release(&buf);
329                 return 0;
330         } else
331 #endif
332         {
333                 struct grep_source gs;
334                 int hit;
335
336                 grep_source_init(&gs, GREP_SOURCE_FILE, buf.buf, filename, filename);
337                 strbuf_release(&buf);
338                 hit = grep_source(opt, &gs);
339
340                 grep_source_clear(&gs);
341                 return hit;
342         }
343 }
344
345 static void append_path(struct grep_opt *opt, const void *data, size_t len)
346 {
347         struct string_list *path_list = opt->output_priv;
348
349         if (len == 1 && *(const char *)data == '\0')
350                 return;
351         string_list_append(path_list, xstrndup(data, len));
352 }
353
354 static void run_pager(struct grep_opt *opt, const char *prefix)
355 {
356         struct string_list *path_list = opt->output_priv;
357         const char **argv = xmalloc(sizeof(const char *) * (path_list->nr + 1));
358         int i, status;
359
360         for (i = 0; i < path_list->nr; i++)
361                 argv[i] = path_list->items[i].string;
362         argv[path_list->nr] = NULL;
363
364         status = run_command_v_opt_cd_env(argv, RUN_USING_SHELL, prefix, NULL);
365         if (status)
366                 exit(status);
367         free(argv);
368 }
369
370 static int grep_cache(struct grep_opt *opt, const struct pathspec *pathspec, int cached)
371 {
372         int hit = 0;
373         int nr;
374         read_cache();
375
376         for (nr = 0; nr < active_nr; nr++) {
377                 const struct cache_entry *ce = active_cache[nr];
378                 if (!S_ISREG(ce->ce_mode))
379                         continue;
380                 if (!ce_path_match(ce, pathspec, NULL))
381                         continue;
382                 /*
383                  * If CE_VALID is on, we assume worktree file and its cache entry
384                  * are identical, even if worktree file has been modified, so use
385                  * cache version instead
386                  */
387                 if (cached || (ce->ce_flags & CE_VALID) || ce_skip_worktree(ce)) {
388                         if (ce_stage(ce))
389                                 continue;
390                         hit |= grep_sha1(opt, ce->sha1, ce->name, 0, ce->name);
391                 }
392                 else
393                         hit |= grep_file(opt, ce->name);
394                 if (ce_stage(ce)) {
395                         do {
396                                 nr++;
397                         } while (nr < active_nr &&
398                                  !strcmp(ce->name, active_cache[nr]->name));
399                         nr--; /* compensate for loop control */
400                 }
401                 if (hit && opt->status_only)
402                         break;
403         }
404         return hit;
405 }
406
407 static int grep_tree(struct grep_opt *opt, const struct pathspec *pathspec,
408                      struct tree_desc *tree, struct strbuf *base, int tn_len,
409                      int check_attr)
410 {
411         int hit = 0;
412         enum interesting match = entry_not_interesting;
413         struct name_entry entry;
414         int old_baselen = base->len;
415
416         while (tree_entry(tree, &entry)) {
417                 int te_len = tree_entry_len(&entry);
418
419                 if (match != all_entries_interesting) {
420                         match = tree_entry_interesting(&entry, base, tn_len, pathspec);
421                         if (match == all_entries_not_interesting)
422                                 break;
423                         if (match == entry_not_interesting)
424                                 continue;
425                 }
426
427                 strbuf_add(base, entry.path, te_len);
428
429                 if (S_ISREG(entry.mode)) {
430                         hit |= grep_sha1(opt, entry.sha1, base->buf, tn_len,
431                                          check_attr ? base->buf + tn_len : NULL);
432                 }
433                 else if (S_ISDIR(entry.mode)) {
434                         enum object_type type;
435                         struct tree_desc sub;
436                         void *data;
437                         unsigned long size;
438
439                         data = lock_and_read_sha1_file(entry.sha1, &type, &size);
440                         if (!data)
441                                 die(_("unable to read tree (%s)"),
442                                     sha1_to_hex(entry.sha1));
443
444                         strbuf_addch(base, '/');
445                         init_tree_desc(&sub, data, size);
446                         hit |= grep_tree(opt, pathspec, &sub, base, tn_len,
447                                          check_attr);
448                         free(data);
449                 }
450                 strbuf_setlen(base, old_baselen);
451
452                 if (hit && opt->status_only)
453                         break;
454         }
455         return hit;
456 }
457
458 static int grep_object(struct grep_opt *opt, const struct pathspec *pathspec,
459                        struct object *obj, const char *name, const char *path)
460 {
461         if (obj->type == OBJ_BLOB)
462                 return grep_sha1(opt, obj->sha1, name, 0, path);
463         if (obj->type == OBJ_COMMIT || obj->type == OBJ_TREE) {
464                 struct tree_desc tree;
465                 void *data;
466                 unsigned long size;
467                 struct strbuf base;
468                 int hit, len;
469
470                 grep_read_lock();
471                 data = read_object_with_reference(obj->sha1, tree_type,
472                                                   &size, NULL);
473                 grep_read_unlock();
474
475                 if (!data)
476                         die(_("unable to read tree (%s)"), sha1_to_hex(obj->sha1));
477
478                 len = name ? strlen(name) : 0;
479                 strbuf_init(&base, PATH_MAX + len + 1);
480                 if (len) {
481                         strbuf_add(&base, name, len);
482                         strbuf_addch(&base, ':');
483                 }
484                 init_tree_desc(&tree, data, size);
485                 hit = grep_tree(opt, pathspec, &tree, &base, base.len,
486                                 obj->type == OBJ_COMMIT);
487                 strbuf_release(&base);
488                 free(data);
489                 return hit;
490         }
491         die(_("unable to grep from object of type %s"), typename(obj->type));
492 }
493
494 static int grep_objects(struct grep_opt *opt, const struct pathspec *pathspec,
495                         const struct object_array *list)
496 {
497         unsigned int i;
498         int hit = 0;
499         const unsigned int nr = list->nr;
500
501         for (i = 0; i < nr; i++) {
502                 struct object *real_obj;
503                 real_obj = deref_tag(list->objects[i].item, NULL, 0);
504                 if (grep_object(opt, pathspec, real_obj, list->objects[i].name, list->objects[i].path)) {
505                         hit = 1;
506                         if (opt->status_only)
507                                 break;
508                 }
509         }
510         return hit;
511 }
512
513 static int grep_directory(struct grep_opt *opt, const struct pathspec *pathspec,
514                           int exc_std)
515 {
516         struct dir_struct dir;
517         int i, hit = 0;
518
519         memset(&dir, 0, sizeof(dir));
520         if (exc_std)
521                 setup_standard_excludes(&dir);
522
523         fill_directory(&dir, pathspec);
524         for (i = 0; i < dir.nr; i++) {
525                 if (!dir_path_match(dir.entries[i], pathspec, 0, NULL))
526                         continue;
527                 hit |= grep_file(opt, dir.entries[i]->name);
528                 if (hit && opt->status_only)
529                         break;
530         }
531         return hit;
532 }
533
534 static int context_callback(const struct option *opt, const char *arg,
535                             int unset)
536 {
537         struct grep_opt *grep_opt = opt->value;
538         int value;
539         const char *endp;
540
541         if (unset) {
542                 grep_opt->pre_context = grep_opt->post_context = 0;
543                 return 0;
544         }
545         value = strtol(arg, (char **)&endp, 10);
546         if (*endp) {
547                 return error(_("switch `%c' expects a numerical value"),
548                              opt->short_name);
549         }
550         grep_opt->pre_context = grep_opt->post_context = value;
551         return 0;
552 }
553
554 static int file_callback(const struct option *opt, const char *arg, int unset)
555 {
556         struct grep_opt *grep_opt = opt->value;
557         int from_stdin = !strcmp(arg, "-");
558         FILE *patterns;
559         int lno = 0;
560         struct strbuf sb = STRBUF_INIT;
561
562         patterns = from_stdin ? stdin : fopen(arg, "r");
563         if (!patterns)
564                 die_errno(_("cannot open '%s'"), arg);
565         while (strbuf_getline(&sb, patterns, '\n') == 0) {
566                 /* ignore empty line like grep does */
567                 if (sb.len == 0)
568                         continue;
569
570                 append_grep_pat(grep_opt, sb.buf, sb.len, arg, ++lno,
571                                 GREP_PATTERN);
572         }
573         if (!from_stdin)
574                 fclose(patterns);
575         strbuf_release(&sb);
576         return 0;
577 }
578
579 static int not_callback(const struct option *opt, const char *arg, int unset)
580 {
581         struct grep_opt *grep_opt = opt->value;
582         append_grep_pattern(grep_opt, "--not", "command line", 0, GREP_NOT);
583         return 0;
584 }
585
586 static int and_callback(const struct option *opt, const char *arg, int unset)
587 {
588         struct grep_opt *grep_opt = opt->value;
589         append_grep_pattern(grep_opt, "--and", "command line", 0, GREP_AND);
590         return 0;
591 }
592
593 static int open_callback(const struct option *opt, const char *arg, int unset)
594 {
595         struct grep_opt *grep_opt = opt->value;
596         append_grep_pattern(grep_opt, "(", "command line", 0, GREP_OPEN_PAREN);
597         return 0;
598 }
599
600 static int close_callback(const struct option *opt, const char *arg, int unset)
601 {
602         struct grep_opt *grep_opt = opt->value;
603         append_grep_pattern(grep_opt, ")", "command line", 0, GREP_CLOSE_PAREN);
604         return 0;
605 }
606
607 static int pattern_callback(const struct option *opt, const char *arg,
608                             int unset)
609 {
610         struct grep_opt *grep_opt = opt->value;
611         append_grep_pattern(grep_opt, arg, "-e option", 0, GREP_PATTERN);
612         return 0;
613 }
614
615 static int help_callback(const struct option *opt, const char *arg, int unset)
616 {
617         return -1;
618 }
619
620 int cmd_grep(int argc, const char **argv, const char *prefix)
621 {
622         int hit = 0;
623         int cached = 0, untracked = 0, opt_exclude = -1;
624         int seen_dashdash = 0;
625         int external_grep_allowed__ignored;
626         const char *show_in_pager = NULL, *default_pager = "dummy";
627         struct grep_opt opt;
628         struct object_array list = OBJECT_ARRAY_INIT;
629         struct pathspec pathspec;
630         struct string_list path_list = STRING_LIST_INIT_NODUP;
631         int i;
632         int dummy;
633         int use_index = 1;
634         int pattern_type_arg = GREP_PATTERN_TYPE_UNSPECIFIED;
635
636         struct option options[] = {
637                 OPT_BOOL(0, "cached", &cached,
638                         N_("search in index instead of in the work tree")),
639                 OPT_NEGBIT(0, "no-index", &use_index,
640                          N_("find in contents not managed by git"), 1),
641                 OPT_BOOL(0, "untracked", &untracked,
642                         N_("search in both tracked and untracked files")),
643                 OPT_SET_INT(0, "exclude-standard", &opt_exclude,
644                             N_("ignore files specified via '.gitignore'"), 1),
645                 OPT_GROUP(""),
646                 OPT_BOOL('v', "invert-match", &opt.invert,
647                         N_("show non-matching lines")),
648                 OPT_BOOL('i', "ignore-case", &opt.ignore_case,
649                         N_("case insensitive matching")),
650                 OPT_BOOL('w', "word-regexp", &opt.word_regexp,
651                         N_("match patterns only at word boundaries")),
652                 OPT_SET_INT('a', "text", &opt.binary,
653                         N_("process binary files as text"), GREP_BINARY_TEXT),
654                 OPT_SET_INT('I', NULL, &opt.binary,
655                         N_("don't match patterns in binary files"),
656                         GREP_BINARY_NOMATCH),
657                 OPT_BOOL(0, "textconv", &opt.allow_textconv,
658                          N_("process binary files with textconv filters")),
659                 { OPTION_INTEGER, 0, "max-depth", &opt.max_depth, N_("depth"),
660                         N_("descend at most <depth> levels"), PARSE_OPT_NONEG,
661                         NULL, 1 },
662                 OPT_GROUP(""),
663                 OPT_SET_INT('E', "extended-regexp", &pattern_type_arg,
664                             N_("use extended POSIX regular expressions"),
665                             GREP_PATTERN_TYPE_ERE),
666                 OPT_SET_INT('G', "basic-regexp", &pattern_type_arg,
667                             N_("use basic POSIX regular expressions (default)"),
668                             GREP_PATTERN_TYPE_BRE),
669                 OPT_SET_INT('F', "fixed-strings", &pattern_type_arg,
670                             N_("interpret patterns as fixed strings"),
671                             GREP_PATTERN_TYPE_FIXED),
672                 OPT_SET_INT('P', "perl-regexp", &pattern_type_arg,
673                             N_("use Perl-compatible regular expressions"),
674                             GREP_PATTERN_TYPE_PCRE),
675                 OPT_GROUP(""),
676                 OPT_BOOL('n', "line-number", &opt.linenum, N_("show line numbers")),
677                 OPT_NEGBIT('h', NULL, &opt.pathname, N_("don't show filenames"), 1),
678                 OPT_BIT('H', NULL, &opt.pathname, N_("show filenames"), 1),
679                 OPT_NEGBIT(0, "full-name", &opt.relative,
680                         N_("show filenames relative to top directory"), 1),
681                 OPT_BOOL('l', "files-with-matches", &opt.name_only,
682                         N_("show only filenames instead of matching lines")),
683                 OPT_BOOL(0, "name-only", &opt.name_only,
684                         N_("synonym for --files-with-matches")),
685                 OPT_BOOL('L', "files-without-match",
686                         &opt.unmatch_name_only,
687                         N_("show only the names of files without match")),
688                 OPT_BOOL('z', "null", &opt.null_following_name,
689                         N_("print NUL after filenames")),
690                 OPT_BOOL('c', "count", &opt.count,
691                         N_("show the number of matches instead of matching lines")),
692                 OPT__COLOR(&opt.color, N_("highlight matches")),
693                 OPT_BOOL(0, "break", &opt.file_break,
694                         N_("print empty line between matches from different files")),
695                 OPT_BOOL(0, "heading", &opt.heading,
696                         N_("show filename only once above matches from same file")),
697                 OPT_GROUP(""),
698                 OPT_CALLBACK('C', "context", &opt, N_("n"),
699                         N_("show <n> context lines before and after matches"),
700                         context_callback),
701                 OPT_INTEGER('B', "before-context", &opt.pre_context,
702                         N_("show <n> context lines before matches")),
703                 OPT_INTEGER('A', "after-context", &opt.post_context,
704                         N_("show <n> context lines after matches")),
705                 OPT_NUMBER_CALLBACK(&opt, N_("shortcut for -C NUM"),
706                         context_callback),
707                 OPT_BOOL('p', "show-function", &opt.funcname,
708                         N_("show a line with the function name before matches")),
709                 OPT_BOOL('W', "function-context", &opt.funcbody,
710                         N_("show the surrounding function")),
711                 OPT_GROUP(""),
712                 OPT_CALLBACK('f', NULL, &opt, N_("file"),
713                         N_("read patterns from file"), file_callback),
714                 { OPTION_CALLBACK, 'e', NULL, &opt, N_("pattern"),
715                         N_("match <pattern>"), PARSE_OPT_NONEG, pattern_callback },
716                 { OPTION_CALLBACK, 0, "and", &opt, NULL,
717                   N_("combine patterns specified with -e"),
718                   PARSE_OPT_NOARG | PARSE_OPT_NONEG, and_callback },
719                 OPT_BOOL(0, "or", &dummy, ""),
720                 { OPTION_CALLBACK, 0, "not", &opt, NULL, "",
721                   PARSE_OPT_NOARG | PARSE_OPT_NONEG, not_callback },
722                 { OPTION_CALLBACK, '(', NULL, &opt, NULL, "",
723                   PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
724                   open_callback },
725                 { OPTION_CALLBACK, ')', NULL, &opt, NULL, "",
726                   PARSE_OPT_NOARG | PARSE_OPT_NONEG | PARSE_OPT_NODASH,
727                   close_callback },
728                 OPT__QUIET(&opt.status_only,
729                            N_("indicate hit with exit status without output")),
730                 OPT_BOOL(0, "all-match", &opt.all_match,
731                         N_("show only matches from files that match all patterns")),
732                 { OPTION_SET_INT, 0, "debug", &opt.debug, NULL,
733                   N_("show parse tree for grep expression"),
734                   PARSE_OPT_NOARG | PARSE_OPT_HIDDEN, NULL, 1 },
735                 OPT_GROUP(""),
736                 { OPTION_STRING, 'O', "open-files-in-pager", &show_in_pager,
737                         N_("pager"), N_("show matching files in the pager"),
738                         PARSE_OPT_OPTARG, NULL, (intptr_t)default_pager },
739                 OPT_BOOL(0, "ext-grep", &external_grep_allowed__ignored,
740                          N_("allow calling of grep(1) (ignored by this build)")),
741                 { OPTION_CALLBACK, 0, "help-all", &options, NULL, N_("show usage"),
742                   PARSE_OPT_HIDDEN | PARSE_OPT_NOARG, help_callback },
743                 OPT_END()
744         };
745
746         /*
747          * 'git grep -h', unlike 'git grep -h <pattern>', is a request
748          * to show usage information and exit.
749          */
750         if (argc == 2 && !strcmp(argv[1], "-h"))
751                 usage_with_options(grep_usage, options);
752
753         init_grep_defaults();
754         git_config(grep_cmd_config, NULL);
755         grep_init(&opt, prefix);
756
757         /*
758          * If there is no -- then the paths must exist in the working
759          * tree.  If there is no explicit pattern specified with -e or
760          * -f, we take the first unrecognized non option to be the
761          * pattern, but then what follows it must be zero or more
762          * valid refs up to the -- (if exists), and then existing
763          * paths.  If there is an explicit pattern, then the first
764          * unrecognized non option is the beginning of the refs list
765          * that continues up to the -- (if exists), and then paths.
766          */
767         argc = parse_options(argc, argv, prefix, options, grep_usage,
768                              PARSE_OPT_KEEP_DASHDASH |
769                              PARSE_OPT_STOP_AT_NON_OPTION |
770                              PARSE_OPT_NO_INTERNAL_HELP);
771         grep_commit_pattern_type(pattern_type_arg, &opt);
772
773         if (use_index && !startup_info->have_repository)
774                 /* die the same way as if we did it at the beginning */
775                 setup_git_directory();
776
777         /*
778          * skip a -- separator; we know it cannot be
779          * separating revisions from pathnames if
780          * we haven't even had any patterns yet
781          */
782         if (argc > 0 && !opt.pattern_list && !strcmp(argv[0], "--")) {
783                 argv++;
784                 argc--;
785         }
786
787         /* First unrecognized non-option token */
788         if (argc > 0 && !opt.pattern_list) {
789                 append_grep_pattern(&opt, argv[0], "command line", 0,
790                                     GREP_PATTERN);
791                 argv++;
792                 argc--;
793         }
794
795         if (show_in_pager == default_pager)
796                 show_in_pager = git_pager(1);
797         if (show_in_pager) {
798                 opt.color = 0;
799                 opt.name_only = 1;
800                 opt.null_following_name = 1;
801                 opt.output_priv = &path_list;
802                 opt.output = append_path;
803                 string_list_append(&path_list, show_in_pager);
804                 use_threads = 0;
805         }
806
807         if (!opt.pattern_list)
808                 die(_("no pattern given."));
809         if (!opt.fixed && opt.ignore_case)
810                 opt.regflags |= REG_ICASE;
811
812         compile_grep_patterns(&opt);
813
814         /* Check revs and then paths */
815         for (i = 0; i < argc; i++) {
816                 const char *arg = argv[i];
817                 unsigned char sha1[20];
818                 struct object_context oc;
819                 /* Is it a rev? */
820                 if (!get_sha1_with_context(arg, 0, sha1, &oc)) {
821                         struct object *object = parse_object_or_die(sha1, arg);
822                         if (!seen_dashdash)
823                                 verify_non_filename(prefix, arg);
824                         add_object_array_with_path(object, arg, &list, oc.mode, oc.path);
825                         continue;
826                 }
827                 if (!strcmp(arg, "--")) {
828                         i++;
829                         seen_dashdash = 1;
830                 }
831                 break;
832         }
833
834 #ifndef NO_PTHREADS
835         if (list.nr || cached || online_cpus() == 1)
836                 use_threads = 0;
837 #else
838         use_threads = 0;
839 #endif
840
841 #ifndef NO_PTHREADS
842         if (use_threads) {
843                 if (!(opt.name_only || opt.unmatch_name_only || opt.count)
844                     && (opt.pre_context || opt.post_context ||
845                         opt.file_break || opt.funcbody))
846                         skip_first_line = 1;
847                 start_threads(&opt);
848         }
849 #endif
850
851         /* The rest are paths */
852         if (!seen_dashdash) {
853                 int j;
854                 for (j = i; j < argc; j++)
855                         verify_filename(prefix, argv[j], j == i);
856         }
857
858         parse_pathspec(&pathspec, 0,
859                        PATHSPEC_PREFER_CWD |
860                        (opt.max_depth != -1 ? PATHSPEC_MAXDEPTH_VALID : 0),
861                        prefix, argv + i);
862         pathspec.max_depth = opt.max_depth;
863         pathspec.recursive = 1;
864
865         if (show_in_pager && (cached || list.nr))
866                 die(_("--open-files-in-pager only works on the worktree"));
867
868         if (show_in_pager && opt.pattern_list && !opt.pattern_list->next) {
869                 const char *pager = path_list.items[0].string;
870                 int len = strlen(pager);
871
872                 if (len > 4 && is_dir_sep(pager[len - 5]))
873                         pager += len - 4;
874
875                 if (opt.ignore_case && !strcmp("less", pager))
876                         string_list_append(&path_list, "-I");
877
878                 if (!strcmp("less", pager) || !strcmp("vi", pager)) {
879                         struct strbuf buf = STRBUF_INIT;
880                         strbuf_addf(&buf, "+/%s%s",
881                                         strcmp("less", pager) ? "" : "*",
882                                         opt.pattern_list->pattern);
883                         string_list_append(&path_list, buf.buf);
884                         strbuf_detach(&buf, NULL);
885                 }
886         }
887
888         if (!show_in_pager && !opt.status_only)
889                 setup_pager();
890
891         if (!use_index && (untracked || cached))
892                 die(_("--cached or --untracked cannot be used with --no-index."));
893
894         if (!use_index || untracked) {
895                 int use_exclude = (opt_exclude < 0) ? use_index : !!opt_exclude;
896                 if (list.nr)
897                         die(_("--no-index or --untracked cannot be used with revs."));
898                 hit = grep_directory(&opt, &pathspec, use_exclude);
899         } else if (0 <= opt_exclude) {
900                 die(_("--[no-]exclude-standard cannot be used for tracked contents."));
901         } else if (!list.nr) {
902                 if (!cached)
903                         setup_work_tree();
904
905                 hit = grep_cache(&opt, &pathspec, cached);
906         } else {
907                 if (cached)
908                         die(_("both --cached and trees are given."));
909                 hit = grep_objects(&opt, &pathspec, &list);
910         }
911
912         if (use_threads)
913                 hit |= wait_all();
914         if (hit && show_in_pager)
915                 run_pager(&opt, prefix);
916         free_grep_patterns(&opt);
917         return !hit;
918 }